Fix subtyping relation
Fix subtyping relation

jjdekker/libminizinc,jjdekker/libminizinc,jjdekker/libminizinc,tias/libminizinc,nathanielbaxter/libminizinc,tias/libminizinc,jjdekker/libminizinc,nathanielbaxter/libminizinc,nathanielbaxter/libminizinc,nathanielbaxter/libminizinc